This invention relates to a method of alleviating the symptoms associated with chronic fatigue syndrome through the use of antiviral agents.
Chronic fatigue syndrome (CFS) is a disorder which, until recently, had no formalized name, received little attention and was believed by the majority of the medical community to be a psychological rather than medical disorder. However, as information about the disorder has been disseminated, the symptoms associated with the disorder, as well as the growing number of people afflicted with this disorder, have steadily increased to alarming proportions. In fact, CFS is being reported with increasing frequency throughout the world.
Chronic fatigue syndrome is a puzzling, exasperating illness whereby previously healthy, vigorous and productive young or middle-aged adults are suddenly afflicted with a persistent, overwhelming fatigue. When such a severe debilitating fatigue extends beyond six months and psychiatric disease is excluded, the condition has been termed xe2x80x9cchronic fatigue syndrome.xe2x80x9d Despite the number of people afflicted with chronic fatigue syndrome and the recent research attention, to date, the cause of the disorder remains unknown.
The medical community has only recently defined the term xe2x80x9cchronic fatigue syndromexe2x80x9d to have a distinct and well-defined meaning. In the Journal of the Royal Society of Medicine, Vol. 84, February, 1991, chronic fatigue syndrome is defined as:
xe2x80x9cA fatigue which is the principal symptom, which has a definite onset, and is severe, disabling and affects both physical and mental functioning, and furthermore that fatigue should have been present for a minimum of six months at which it was present for more than 50% of the time.xe2x80x9d
One or more of the following symptoms are generally associated with the syndrome, such as sleep disturbances (changes in the duration of sleep and/or quality of sleep), impairments in concentration and short-term memory, chronic and recurrent low-grade fever, and musculoskeletal pain. The changes in the duration of sleep could be hypersomnia or increased sleep, or insomnia or reduced sleep. The changes of the quality of sleep are contemplated to be due to a decrease of REM sleep. There is also generally a restriction or lack of ability to perform an activity in the manner or within the range considered normal for a healthy human being, (resulting from loss of psychological or physiological function). There is further a definite persistent change from a previous level of functioning.
Mood disturbances such as depressed mood, and anhedonia, anxious mood, emotional stability, irritability, and severity of the mood disturbances should be assessed on standards scales. For diagnosis purposes, a patient""s symptoms should be evaluated to determine whether such symptoms are attributed by a psychological condition, such as a depressive disorder rather than chronic fatigue syndrome. It should thus be determined whether the disorder is sufficient to meet the diagnostic criteria for major depressive disorders. In CFS patients, myalgia, which is pain or aching felt in the muscles, should be disproportionate to exertion. Such myalgia should be distinguished from feelings of weakness and pain felt in other areas such as the joints. Certain patients should be excluded from the definition of CFS, such as patients with established medical conditions known to produce chronic fatigue such as severe anemia. Additionally, patients with schizophrenia, manic depressive illness, substance abuse, eating disorders, or proven organic brain disease should be excluded as chronic fatigue syndrome sufferers. However, other generalized psychiatric disorders may be attributed to chronic fatigue syndrome.
A variety of treatments have been suggested and utilized for the treatment of chronic fatigue syndrome. In U.S. Pat. No. 5,312,817, there is described a treatment of the chronic fatigue syndrome wherein a pharmaceutically-acceptable cholinesterase inhibitor or a prodrug therefore is administered for the treatment of fatigue syndromes. This treatment is based on the understanding that the mechanism of the fatigue could be an imbalance in the cholinergic nicotinic transmitter system, both peripherally and centrally, which decreases the acetylcholine in the central and peripheral synapses. However, this therapy has proven ineffective, as this mechanism does not properly describe the etiology of chronic fatigue syndrome.
In a further example, U.S. Pat. No. 5,055,296 discloses a treatment involving the administration of mammalian liver extract. Yet another example is provided in U.S. Pat. No. 5,013,739, whereby an opiate receptor antagonist is administered as a treatment option. In addition, a variety of drugs have been prescribed for symptomatic relief including non-steroidal anti-inflammatory drugs, tricyclic anti-depressants, sleep-inducing drugs, tranquilizers, anti-anxiety and stress-relieving drugs such as androstenediol and androstenetriol. Such symptomatic treatment efforts, while providing temporary relief for one of the associated symptoms, have in general provided no long-term treatment of the disorder as a whole.
In addition to the physical pain associated with this disorder, there is also a severe mental and emotional toll placed on the CFS sufferer. As a result of the prolonged and debilitating fatigue, and flu-like symptoms, CFS sufferers are forced to reduce their level of activity, and are often unable to lead what would be considered a normal life.
Accordingly, there is a genuine need for a method of treating chronic fatigue syndrome with a reliable, and effective technique which allows a CFS sufferer to regain a normal level of activity without the associated persistent fatigue characterized by the disorder.
It would be desirable to provide a method for alleviating the symptoms associated with chronic fatigue syndrome by administering antiviral agents to target the cause of the disorder. It would further be desirable to provide a treatment for chronic fatigue syndrome through administration of an antiviral drug which is directed to the cause of chronic fatigue syndrome rather than one that addresses a particular condition or symptom. It would be yet further desirable to provide a long-term treatment approach whereby chronic fatigue sufferers could resume a normal level of activity without experiencing extreme fatigue.
In carrying out the above objects, a method is disclosed for alleviating the symptoms of chronic fatigue syndrome, including administering to a patient in need there of, a therapeutically effective amount of one or more pharmaceutically acceptable antiviral agents, wherein the one or more antiviral agents are selected from the group consisting of acyclovir, ganciclovir, valacyclovir, famciclovir, cidofovir, and pharmaceutically acceptable derivatives and mixtures thereof.
There is further disclosed a method of diagnosing chronic fatigue syndrome (CFS) in a patient, including the steps of: evaluating the patient for serologic evidence of Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) infection; and monitoring the patient for T-wave abnormalities by 24-hour electrocardiographic (Holter) monitoring to document the persistent cardiac pathology which is the basis of the CFS. The serologic evidence of EBV and HCMV is obtained by studying the level of antibodies of EBV and HCMV to detect the presence of active and persistent multiplication of either or both of the viruses. In conjunction therewith, tests are conducted to verify the existence of a cardiomyopathy in the CFS patient. Based on the results of the tests and the determination of the cause of CFS, the patient is administered a specific antiviral agent suitable for EBV, HCMV or the combination. Following initial antiviral treatment, supplemental tests are conducted to check for recurrent CFS to determine an appropriate treatment period for the patient to achieve continued alleviation of the CFS symptoms.
There is yet another method of diagnosing CFS in a patient including the steps of: evaluating the patient for serologic evidence by HCMV, evaluating assays for non-structural early gene products; and monitoring the patient for T-wave abnormalities by 24-hour Holter monitoring to document the persistent cardiac pathology which is the basis of the CFS.
The above objects and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention.